CComHeap Class

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This class implements IAtlMemMgr using the COM memory allocation functions.

Important

This class and its members cannot be used in applications that execute in the Windows Runtime.

Syntax

class CComHeap : public IAtlMemMgr

Members

Public Methods

Name Description
CComHeap::Allocate Call this method to allocate a block of memory.
CComHeap::Free Call this method to free a block of memory allocated by this memory manager.
CComHeap::GetSize Call this method to get the allocated size of a memory block allocated by this memory manager.
CComHeap::Reallocate Call this method to reallocate memory allocated by this memory manager.

Remarks

CComHeap implements memory allocation functions using the COM allocation functions, including CoTaskMemAlloc, CoTaskMemFree, IMalloc::GetSize, and CoTaskMemRealloc. The maximum amount of memory that can be allocated is equal to INT_MAX (2147483647) bytes.

Example

See the example for IAtlMemMgr.

Inheritance Hierarchy

IAtlMemMgr

CComHeap

Requirements

Header: ATLComMem.h

CComHeap::Allocate

Call this method to allocate a block of memory.

virtual __declspec(allocator) void* Allocate(size_t nBytes) throw();

Parameters

nBytes
The requested number of bytes in the new memory block.

Return Value

Returns a pointer to the start of the newly allocated memory block.

Remarks

Call CComHeap::Free or CComHeap::Reallocate to free the memory allocated by this method.

Implemented using CoTaskMemAlloc.

CComHeap::Free

Call this method to free a block of memory allocated by this memory manager.

virtual void Free(void* p) throw();

Parameters

p
Pointer to memory previously allocated by this memory manager. NULL is a valid value and does nothing.

Remarks

Implemented using CoTaskMemFree.

CComHeap::GetSize

Call this method to get the allocated size of a memory block allocated by this memory manager.

virtual size_t GetSize(void* p) throw();

Parameters

p
Pointer to memory previously allocated by this memory manager.

Return Value

Returns the size of the allocated memory block in bytes.

Remarks

Implemented using IMalloc::GetSize.

CComHeap::Reallocate

Call this method to reallocate memory allocated by this memory manager.

virtual __declspec(allocator) void* Reallocate(void* p, size_t nBytes) throw();

Parameters

p
Pointer to memory previously allocated by this memory manager.

nBytes
The requested number of bytes in the new memory block.

Return Value

Returns a pointer to the start of the newly allocated memory block.

Remarks

Call CComHeap::Free to free the memory allocated by this method.

Implemented using CoTaskMemRealloc.

See Also

DynamicConsumer Sample
Class Overview
CWin32Heap Class
CLocalHeap Class
CGlobalHeap Class
CCRTHeap Class
IAtlMemMgr Class